During one of the many monster attacks on the city where the story takes place, Silk Koharuno and her two friends attempt to get closer to the monster to get a better view. Unfortunately, the city's protector, UFO-man, comes to the rescue but inadvertently steps on them and crushes the girls to death. Feeling sorry for what he had done, UFO-man blames their deaths on the monster and promises to bring them back to life by lending them his power. However, now they must become the city's protectors as well.
The monsters of the series are born by green alien slime fusing to human beings with the monsters representing their personalities. If the opal-like cores are destroyed or separated the monster will disintegrate into gold particles of light.
Gullmark: Appears in episode 1. Its only known power is having a highly articulate body. It is a homage to Gomess from Ultra Q.
Shupo: Appears in episodes 2 and 3. Its only known power is morphing into a steam engine train. It is a homage to King Joe from Ultra Seven.
Ochuusha: Appears in episode 4. Powers include a syringe on arms, super speed, and stethoscope on the pelvis. It is a homage to Baltan Seijin from the original Ultraman with characteristics of Zetton and Metrojn Seijin.
Megami Mask: Appears in episode 5. Powers include a pair of glue bazookas on the back, wrestling skills, and summonable steel armor. He is a reference to the editor of Megami Magazine, the magazine that publishes the Ultimate Girls manga and his mask is arguably a reference to Ultimate Muscle.
Hachiro: Appears in episode 6. His only known power is a boxing glove on him main pair of tentacles.
Mahler: Appears in episode 7. Powers include burrowing, emitting hypnotic waves from the giant metronome on its face, and a maestro wand. It is a homage to Mochiron from Ultraman Taro.
Dainioh: Appears in episodes 8 and 9. Powers include a club, a constricting bead necklace, a spare body, burrowing by spinning, swimming, and six extra arms in its body. It is a homage Majin from Daimajin.
Mushuusaa: Appears in episode 10. Powers include a pair of scythe arms and a whip tail. It is a homage to Gyaos and Gigan.
Giant Makato: Appears in episodes 11 and 12. He is a homage to super robots such as Mazinger Z and the guyver units from Bio Booster Armor Guyver.
Music
;Opening Theme: "White Heat" by Yozuca* ;Ending Theme: "3 Sentimental" by Misato Fukuen